YOUR ULTIMATE RESOURCE ON FETAL MALPOSITION AND MALPRESENTATION

Introduction

Fetal malposition and malpresentation are two terms used in obstetrics to describe abnormal positions of the fetus during pregnancy and labor. These conditions can potentially complicate the process of childbirth and may require medical intervention.

Fetal malposition refers to the abnormal positioning of the fetus within the uterus. Normally, the baby is positioned head-down (cephalic presentation) with its back facing the mother’s abdomen. However, in some cases, the fetus may assume a different position, leading to a malposition. The most common malpositions include:

1. Breech presentation: This occurs when the baby’s buttocks or feet are positioned to be delivered first instead of the head. Breech presentations occur in approximately 3-4% of full-term pregnancies.

2. Transverse lie: In this position, the baby lies horizontally across the uterus, with its shoulder or back presenting towards the birth canal. Transverse lies are relatively rare and occur in less than 1% of pregnancies.

3. Occiput posterior position: Also known as “sunny-side-up” or “back-to-back,” this position occurs when the baby’s head is down but facing forward, towards the mother’s abdomen rather than her spine. Occiput posterior positions occur in around 20% of labors.

Malpresentation refers to any abnormal presentation of the fetal body parts during labor. While malposition refers specifically to the overall position of the fetus, malpresentation focuses on specific body parts that present first at delivery. Some examples of malpresentation include:

1. Face presentation: In this case, the baby’s face presents first instead of the vertex (top) of the head. Face presentations occur in about 1 in every 600-800 births.

2. Brow presentation: This occurs when the baby’s forehead is positioned to be delivered first instead of the vertex or face. Brow presentations are relatively rare and account for less than 1% of deliveries.

3. Shoulder presentation: In shoulder presentations, the baby’s shoulder or arm presents first at the birth canal. This is a rare occurrence, happening in less than 1% of pregnancies.

Fetal malposition and malpresentation can pose challenges during labor and delivery. They may increase the risk of complications such as prolonged labor, fetal distress, umbilical cord prolapse, and birth injuries. In some cases, medical interventions such as external cephalic version (ECV), where the healthcare provider manually tries to turn the baby into a head-down position, or cesarean section may be necessary to ensure a safe delivery.

 

Types of fetal malposition explained

Fetal malposition refers to the abnormal positioning of the fetus within the uterus during pregnancy. It occurs when the baby is not in the optimal position for a smooth and uncomplicated delivery. There are several different types of fetal malposition, each with its own characteristics and potential complications.

1. Occiput Posterior Position (OP): In this malposition, the baby’s head is facing forward, towards the mother’s abdomen, instead of facing backward towards her spine. The occiput refers to the back of the baby’s head. OP position occurs in about 10-20% of pregnancies and can lead to prolonged labor, increased pain for the mother, and an increased risk of instrumental delivery (such as forceps or vacuum extraction) or cesarean section. It may also increase the risk of perineal tears for the mother.

2. Breech Presentation: Breech presentation occurs when the baby’s buttocks or feet are positioned to come out first instead of the head. This occurs in about 3-4% of full-term pregnancies. There are different types of breech presentations, including complete breech (baby’s buttocks down with knees bent), frank breech (baby’s buttocks down with legs straight up), and footling breech (one or both feet down). Breech presentation increases the risk of complications during delivery, such as umbilical cord prolapse, which can lead to oxygen deprivation for the baby. It often requires a planned cesarean section or external cephalic version (ECV) to manually turn the baby into a head-down position.

3. Transverse Lie: Transverse lie occurs when the baby is positioned horizontally across the uterus, with its shoulder or back presenting towards the birth canal. This malposition is relatively rare and occurs in less than 1% of pregnancies at term. Transverse lie poses significant risks during labor, including umbilical cord prolapse and difficulty in delivering the baby’s shoulders. It usually requires a cesarean section for delivery.

4. Face Presentation: Face presentation occurs when the baby’s face is positioned to come out first instead of the top or back of the head. This malposition is relatively uncommon and occurs in about 1 in 600-800 deliveries. Face presentation can lead to prolonged labor, increased risk of instrumental delivery or cesarean section, and potential facial injuries for the baby due to pressure against the birth canal.

5. Compound Presentation: Compound presentation occurs when one or both of the baby’s extremities (such as an arm or hand) are alongside the head during delivery. This malposition can increase the risk of shoulder dystocia, where the baby’s shoulder becomes stuck behind the mother’s pubic bone, potentially leading to birth injuries for both the baby and mother.

6. Asynclitism: Asynclitism refers to a tilted or oblique position of the baby’s head in relation to the mother’s pelvis. It can occur in various directions, such as anterior asynclitism (baby’s head tilted towards the front) or posterior asynclitism (baby’s head tilted towards the back). Asynclitism can prolong labor and increase the risk of instrumental delivery or cesarean section.

It is important to note that fetal malposition does not always result in complications during delivery. In some cases, with proper management and support from healthcare professionals, vaginal delivery can still be achieved safely. However, certain malpositions may require interventions such as cesarean section or other techniques to facilitate a safe delivery.

 

Management of different types of fetal malposition

Managing these different types of fetal malposition requires careful assessment, monitoring, and intervention to ensure a safe delivery for both the mother and the baby.

A) Breech Presentation:

Breech presentation is when the baby’s buttocks or feet are positioned to come out first instead of the head. There are three main types of breech presentations: frank breech (where the baby’s buttocks are positioned to come out first with legs straight up), complete breech (where the baby’s buttocks and feet are positioned to come out first with knees bent), and footling breech (where one or both feet are positioned to come out first).

The management of breech presentation depends on several factors, including gestational age, parity (number of previous pregnancies), and the presence of any complications. In general, there are three main approaches to managing breech presentation:

1. External Cephalic Version (ECV): ECV is a procedure where a healthcare provider uses their hands to manually manipulate the baby’s position from breech to head-down. This procedure is typically performed after 36 weeks of gestation when the baby has enough room to move. ECV has been shown to be successful in turning the baby head-down in about 50-60% of cases.

2. Vaginal Breech Delivery: In certain cases, vaginal delivery may be considered for a breech-presenting baby. However, this approach requires careful evaluation and consideration of several factors, including the size of the baby, position of the baby’s head, and experience of the healthcare provider. Vaginal breech delivery should only be performed by skilled healthcare professionals who have received specific training in this technique.

3. Elective Cesarean Section: In many cases, especially if there are additional risk factors or complications, a planned cesarean section may be recommended for breech presentation. This approach ensures a controlled delivery and reduces the risks associated with vaginal breech delivery, such as head entrapment or cord prolapse.

 

B) Transverse Lie:

Transverse lie refers to a fetal position where the baby is lying horizontally across the uterus, with the head on one side and the buttocks on the other side. This position can pose risks during labor and delivery, including umbilical cord compression and difficulties in progressing through the birth canal.

The management of transverse lie depends on several factors, including gestational age, the presence of any complications, and the ability to manually manipulate the baby’s position. The following approaches may be considered:

1. External Cephalic Version (ECV): Similar to breech presentation, ECV can be attempted to rotate the baby from a transverse lie to a head-down position. However, the success rate of ECV for transverse lie is generally lower compared to breech presentation.

2. Manual Rotation: In some cases, if the baby is not too large and there are no contraindications, a healthcare provider may attempt manual rotation of the baby’s position by applying gentle pressure on the abdomen. This technique should only be performed by experienced healthcare professionals who have received appropriate training.

3. Cesarean Section: If attempts to manually rotate the baby are unsuccessful or if there are additional risk factors or complications, a cesarean section may be recommended for transverse lie. This ensures a safe delivery and minimizes the risks associated with vaginal delivery in this position.

 

C) Occiput Posterior Position:

Occiput posterior (OP) position occurs when the baby’s head is facing forward but is positioned towards the mother’s back instead of facing her spine. This position can lead to prolonged labor, increased pain, and an increased risk of instrumental delivery.

The management of occiput posterior position may involve the following strategies:

1. Positioning and Movement: Encouraging the mother to adopt different positions during labor, such as hands and knees or side-lying, can help facilitate the rotation of the baby’s head. Frequent changes in position and movement can also aid in relieving pressure on the mother’s back and promoting optimal fetal positioning.

2. Manual Rotation: In some cases, a healthcare provider may attempt manual rotation of the baby’s head from occiput posterior to occiput anterior position. This technique should only be performed by experienced healthcare professionals who have received appropriate training.

3. Instrumental Delivery: If the baby remains in occiput posterior position despite attempts at rotation and there are signs of fetal distress or prolonged labor, an instrumental delivery may be considered. This can involve the use of forceps or vacuum extraction to assist with the delivery.

In all cases of fetal malposition, close monitoring of both the mother and the baby is essential. Regular assessments of fetal well-being, including fetal heart rate monitoring and ultrasound examinations, should be conducted to ensure that appropriate interventions are implemented promptly if needed.